Brake mechanism



`lari. 8A, 1924o H. Do'rzER BRAKE ME CHAN SM Filed Jan. 9, 1922 Swuemtoa H06@I lPoTzE/E? Patente-d Jan. 8, 19424.

UNITED STA HUGO DOTZER, OF SEATTLE, WASHINGTON.

BRAKE MEGHANISM. l

Application led January 9, 1922. Serial No. 528,028;v

as exterior, contracting brakesQf-f' The principal object of'. this-invention is to provide an'liexternalybrake .mechanism which may be used onltrucks, automobiles,j trailers, etc.l whichuh'asgno fixed connection= withthe vehicle body, `which is easilyV adv wheels vof automobiles,1and which are lknown,

justable and can be removed without the necessity of'rst removing of the vehicle wheel to which it is applied.v

Another object of the invention resides iny the means for adjusting the tension of the brake band sections. i .y

In accomplishing these and other objects of .the invention, I have p-rovided theimproved details of construction the preferredforms of which are illustrated in the accompanying drawings,lwherein Figure 1 is a plan view of an axle and brake mechanism mounted thereon, accord-A ing to the present invention; one of the drums ,being l.shown in ,section for better illustration.

Figure 2 'is a brake assembly, pendicular -to the drum. s

` Figure 3 is a front view of one of the brake assemblies.

Figure 4 is a perspective view of a set of brake control parts in disassembled relation.

Referring more in detail to the drawings- The present brake mechanism employs the usual brake drums 1 which are secured to the interior faces of the vehicle wheels, designated at 2, at opposite ends of the axle housing 3. About these drums are fitted two, cooperatingl semi-circular brake band sections 44 vw ich are equipped with the usual lining, and are supported in operative, functional position from cover plates 5 pro-' vided for the drums and which are secured to the opposite ends of the non-rotatable axle housing 3. f-

partialsectional view of a taken in aplane that is peryaxial line of the brake V spreading By" adjustment At the back edo'e' of each drum cover. plate, is a rearwardly projecting portion 6 wherein pivot bolts 7 are mounted, and pivotally supported on each of these bolts are two pairsof crossed' levers 8 as shown best in Figure 2. Pins 9 are removably mounted to extend between the inner ends of eachA pair of levers and the rearward ends of the two brake bandv sections 4 4 are looped about these pins and thereby joined thereto. At

ltheir outer ends thevpaired levers are yconc .nected bymeans of an adjusting bolt 10 that secured at its lower end to a pin 11 that ers 8 with -which the band 4 is connected,

and is'slidable at its upper end through a vy-.block-f12` to which the upper yends of the` r-otherset-` of levers is, secured. A spring 13 mounted about thefzbolt,V which bears against the block. V12and pin 11 .to urge them apart, and a wing'nut 14 is threaded onto the outer end of the bolt whereby the movement'of the' links is limited. 4 of the nut 14, the bands 4-`-4 are adjusted with respect to the drum.'v

The 'means employed for actuatingthe brake bands-into braking contact with the v drums .comprises 'levers 18 that are pivotally mounted `between spaced apart wings 19, ex` tending vforwardly Afrom thel drum Acover plates 5.- These levers are fixed upon squared shafts 20that extend vertically, and

revolubly through alined apertures 21 in also through apertures 22v said flanges` an in lshoes 23 that are ends of the two brake band sections, as'- is shown in Figure 2.

`Mounted on the opposite ends of the 'shafts 20 to turn therewith, are cam heads 25 provided with cam surfaced sockets 26 adapted to coact with cam faces 27 on the shoes 23, so that, upon turning the shafts by means of the levers, the bands will be caused to be tightened against the brake drum. In `this construction, the levers ani cam heads are designed for the-most effective operation, and the openings 4through the brake band heads and throughthe wings 19 are circular, order to permit the shafts 20, which are square, to turn therein.

lThe vends of these shafts terminate in threaded end portions 28 whereon thumb 1,480,050A TES PATENT OFFICE.

xtnds between thelower ends-cf the set of fixed to the forward v nuts 29 are mounted to engage the heads 25 to hold the parts in functional relation,

yandcoiled springls 30 are mounted about the shafts between t e wings 19 and shoes 23 to urge the brake band sections normally from braking contact with the drums.

The means for actuating, and through which an equalized braking force is automatically placed on the two mechanisms, consists of a cable 40 which connects the ends of the brake levers 20. This cable is drawn taut, and mounted vto move along the same isa pulle 4l mounted in a block 42 to which a cab e 43 is attached; the latter being extended forwardly to any suitable control mechanism. With the two brake mechanisms so constructed and connected, it

l is apparent that`.tension on the-cable 43 will be transmitted to the' cable 40 and thence to the brake levers.

It is also apparent-that should it require one brake lever to move in a greater arc before the brake bands become effected than is required by the opposite lever, the pulley.

will automatically` shift itself towardthe lever which moves in the greater arc and will, in this way, equalize the tension on the two levers and their brake bands.

It is also apparent that, in this c'onstruc- I tion, no parts of the brake mechanism are attached to the sectional frame, but all are mounted on the drum cover and have no movement relative to the frame, and a constant adjustment may be maintained regardless of the load that may be placed on the vehicle.

Having thusdescribed my invention, what I claim as new therein and desire to secure slidable thereon, and an arm' support extended'from the cover.

2. ln a brake mechanism of the class described, thec-ombination with a brake drum and a stationary cover therefor having wings projecting in spaced relation at one edge thereof, with vertically alined apertures therein, a pair of brake' band sections having ends pivotally supported from the cover, and having cam shoes at their other ends disposed on opposite sides of said wings and having apertures therethrough alined with the wing apertures, a square shaft extended rotatably through said wing and cam shoe apertures, cam heads xed adjustably on the outer ends of the shaft to operatively engage the said shoes, and a shaft rotatin lever fitted between the said wings and s idable on said squared shaft.

3. In a brake mechanismof the class demeedoen scribed, the combination with a. brake drum, a non-rotative cover therefor, a pair or brake bands fitted to the drum and actuating mechanism connected with adjacent ends of said bands, of an adjusting mechanism comprising members supported from the cover, and having connection with the ends of the brake bands, and an adjusting means for retaining said members at set positions.

4r. ln a brake mechanism of the class described, the combination with a brake l drum, a non-rotative'cover therefor, a pair of brake bands fitted to the drum and actuatingmechanism` connected with adjacent ends of said bands, of an adjusting mechanism comprising members arranged in crossed relation upon a pivotal. support extended from the cover member, said members having ends v'connected with thetwo opposite brake bands and an adjustable corrl nection at their opposite ends.

5. ln a brake'mechanism of the class described, the combination with a brake drum, a non-rotative cover therefor and a pair of brake bands tted to the drum of an adjusting mechanism for said bands comprising a supporting member fixed in the cover plate, vcrossed links supported pivotally on saidrnember, having inner ends pivotally connected with opposite brake bands,an adjusting bolt extended between the outer ends fof the links, and a yieldable means for retaining the links in spaced relation.

6. A brake mechanism of the'character described, comprising iny combinatioma vehicle wheel having a brake' drum secured thereto, a non-rotative cover plate for the drum having spaced apart wings projecting be' yond its periphery atxone edge and provided with alining apertures therethrough, of a pair of brake -bands having adjacent ends pivotally lsupported from the coverl plate and having shoes secured to their other ends disposed on opposite sides of the said wings; said shoes having cam-` faces on their outer 'sides` and having apertures therethrough in 'alinement with the wing apertures, a squared shaft extending revolubly through said wing and shoe apertures, cam heads mounted on the ends of said shaft engageable with the cam facesof said shoes whereby the latter will be actuated inwardly on revolving they shaft, nuts mounted on the outer ends` of said shaft to effect and retain adjustment of the cams, a lever mounted on the shaft between the wings operable to rotate the shaft to actuate the bands against the drum and compression springs mounted between the Wings and band shoes to urge the bands from the drum.

7. A brake mechanism of the character described, comprising in combination, a vehicle wheel having a brake drum secured thereto, al non-rotative drum cover plate having an extension projecting. beyond the iao periphery of the drum, a bolt mounted in the said extension, two sets of aired levers centrally pivoted upon the bo t' in crossed relation, a pair of brake band sections mounted to engage opposite sides of the drum and having ends pivotally fixed between the inner ends of paired levers, a block pvotally mounted between the outer ends of one set of links, a pin extending between the ends of the opposite set, a bolt having an end pivotallj7 attached to said pin and extending slidably through said block, a nut on the outer end of 'said bolt adjustable to limit the spread of the levers and a spring mounted on the bolt between the pin and block to urge the levers to retain the brake bands normally disengaged from the drum, and means at the opposite i ends of the bands for drawing the same to braking contact with the drum.

8. A brake mechanism of the character described, comprising in combination, a brake drum, a non-rotative cover plate for the drum having a peripheral extension at its rearward edge and having spaced apart wings projecting from its forward edge, havingr alined apertures therein, a pair of brake band sections mounted to engage opposite faces of the drum, a bolt mounted in the rearward projecting portion of the cover plate, two sets of paired levers centrally pivoted upon the boltl in crossed relation and secured at their inner ends to the brake bands, a block pivotally mounted between the ends of one set of levers, a pin extending between the ends of the other set, a bolt having one end pivotally attached to said pin and extending slidably through said block, an .adjustable nut on the outer end of said bolt for adjusting the spread of the levers, shoes secured to the forward ends of the brake band sections on opposite sides of said wings; said shoes having cam faces on their outer sides and having apertures therethrough in alinement with the wing apertures, a shaft extending revolubly through said wing and shoe apertures, -cam heads mounted adjustably on the outer ends of the shaft to engage Cain faces of said shoes and a lever fixed on the shaft between the wings.I

whereby the shaft ma)7 be rotated for the purpose set forth.

Signed at Seattle, Washington this 3rd day of January, 1922.

HUGO DOTZER. 

